Still not working on
Version: 4.6.0-SNAPSHOT
Build Number: a74896a
Globally uncaught exception is still there.
Adding CLI script which does the repro steps.
Please check the exception thrown by CLI client as well. There is no explaining message at all.

fixed in master
http://git.fedorahosted.org/git/?p=rhq/rhq.git;a=commitdiff;h=af0936f97
time: Fri Feb 1 14:02:40 2013 +0100
commit: af0936f97b11698157731942134e181db6e11af6
author: Jirka Kremser - jkremser@redhat.com
message: [BZ 858282 - Globally uncaught exception when creating duplicate role] RoleManager now explicitly checks whether the role with the same name already exists (without trying to create the role first and then catching the exception like it was done before).
As a consequence of this commit, the CLI now prints nicely the real cause of the problem as well.